Weak coupling of neurons enables very high-frequency and ultra-fast oscillations through the interplay of synchronized phase shifts.

Recently, in the past decade, high-frequency oscillations (HFOs), very high-frequency oscillations (VHFOs), and ultra-fast oscillations (UFOs) were reported in epileptic patients with drug-resistant epilepsy. However, to this day, the physiological origin of these events has yet to be understood. Our study establishes a mathematical framework based on bifurcation theory for investigating the occurrence of VHFOs and UFOs in depth EEG signals of patients with focal epilepsy, focusing on the potential role of reduced connection strength between neurons in an epileptic focus. We demonstrate that synchronization of a weakly coupled network can generate very and ultra high-frequency signals detectable by nearby microelectrodes. In particular, we show that a bistability region enables the persistence of phase-shift synchronized clusters of neurons. This phenomenon is observed for different hippocampal neuron models, including Morris-Lecar, Destexhe-Paré, and an interneuron model. The mechanism seems to be robust for small coupling, and it also persists with random noise affecting the external current. Our findings suggest that weakened neuronal connections could contribute to the production of oscillations with frequencies above 1000 Hz, which could advance our understanding of epilepsy pathology and potentially improve treatment strategies. However, further exploration of various coupling types and complex network models is needed.

We have built a mathematical framework to examine how a reduced neuronal coupling within an epileptic focus could lead to very high-frequency (VHFOs) and ultra-fast oscillations (UFOs) in depth EEG signals. By analyzing weakly coupled neurons, we found a bistability synchronization region where in-phase and anti-phase synchrony persist. These dynamics can be detected as very high-frequency EEG signals. The principle of weak coupling aligns with the disturbances in neuronal connections often observed in epilepsy; moreover, VHFOs are important markers of epileptogenicity. Our findings point to the potential significance of weakened neuronal connections in producing VHFOs and UFOs related to focal epilepsy. This could enhance our understanding of brain disorders. We emphasize the need for further investigations of weakly coupled neurons.

Mycobiomes of two distinct clades of ambrosia gall midges (Diptera: Cecidomyiidae) are species-specific in larvae but similar in nutritive mycelia.

IMPORTANCE: Ambrosia gall midges are endophagous insect herbivores whose larvae live enclosed within a single gall for their entire development period. They may exhibit phytomycetophagy, a remarkable feeding mode that involves the consumption of plant biomass and mycelia of their cultivated gall symbionts. Thus, AGMs are ideal model organisms for studying the role of microorganisms in the evolution of host specificity in insects. However, compared to other fungus-farming insects, insect-fungus mutualism in AGMs has been neglected. Our study is the first to use DNA metabarcoding to characterize the complete mycobiome of the entire system of the gall-forming insects as we profiled gall surfaces, nutritive mycelia, and larvae. Interestingly, larval mycobiomes were significantly different from their nutritive mycelia, although Botryosphaeria dothidea dominated the nutritive mycelia, regardless of the evolutionary separation of the tribes studied. Therefore, we confirmed a long-time hypothesized paradigm for the important evolutionary association of this fungus with AGMs.

Diversity of RNA viruses in the cosmopolitan monoxenous trypanosomatid Leptomonas pyrrhocoris.

BACKGROUND: Trypanosomatids are parasitic flagellates well known because of some representatives infecting humans, domestic animals, and cultural plants. Many trypanosomatid species bear RNA viruses, which, in the case of human pathogens Leishmania spp., influence the course of the disease. One of the close relatives of leishmaniae, Leptomonas pyrrhocoris, has been previously shown to harbor viruses of the groups not documented in other trypanosomatids. At the same time, this species has a worldwide distribution and high prevalence in the natural populations of its cosmopolitan firebug host. It therefore represents an attractive model to study the diversity of RNA viruses. RESULTS: We surveyed 106 axenic cultures of L. pyrrhocoris and found that 64 (60%) of these displayed 2-12 double-stranded RNA fragments. The analysis of next-generation sequencing data revealed four viral groups with seven species, of which up to five were simultaneously detected in a single trypanosomatid isolate. Only two of these species, a tombus-like virus and an Ostravirus, were earlier documented in L. pyrrhocoris. In addition, there were four new species of Leishbuviridae, the family encompassing trypanosomatid-specific viruses, and a new species of Qinviridae, the family previously known only from metatranscriptomes of invertebrates. Currently, this is the only qinvirus with an unambiguously determined host. Our phylogenetic inferences suggest reassortment in the tombus-like virus owing to the interaction of different trypanosomatid strains. Two of the new Leishbuviridae members branch early on the phylogenetic tree of this family and display intermediate stages of genomic segment reduction between insect Phenuiviridae and crown Leishbuviridae. CONCLUSIONS: The unprecedented wide range of viruses in one protist species and the simultaneous presence of up to five viral species in a single Leptomonas pyrrhocoris isolate indicate the uniqueness of this flagellate. This is likely determined by the peculiarity of its firebug host, a highly abundant cosmopolitan species with several habits ensuring wide distribution and profuseness of L. pyrrhocoris, as well as its exposure to a wider spectrum of viruses compared to other trypanosomatids combined with a limited ability to transmit these viruses to its relatives. Thus, L. pyrrhocoris represents a suitable model to study the adoption of new viruses and their relationships with a protist host.

A New Heart-Cutting Method for a Multiplex Quantitative Analysis of Steroid Hormones in Plasma Using 2D-LC/MS/MS Technique.

The aim of the current research was to develop a simple and rapid mass spectrometry-based assay for the determination of 15 steroid hormones in human plasma in a single run, which would be suitable for a routine practice setting. For this purpose, we designed a procedure based on the 2D-liquid chromatography-tandem mass spectrometry with a minimalistic sample pre-treatment. In our arrangement, the preparation of one sample takes only 10 min and can accommodate 40 samples per hour when tested in series. The following analytical run is 18 min long for all steroid hormones. In addition, we developed an independent analytical run for estradiol, significantly increasing the assay accuracy while taking an additional 10 min to perform an analytical run of a sample. The optimized method was applied to a set of human plasma samples, including chylous. Our results indicate the linearity of the method for all steroid hormones with squared regression coefficients R2 ≥ 0.995, within-run and between-run precision (RSD < 6.4%), and an accuracy of 92.9% to 106.2%. The absolute recovery for each analyzed steroid hormone ranged between 101.6% and 116.5%. The method detection limit for 15 steroid hormones ranged between 0.008 nmol/L (2.88 pg/mL) for aldosterone and 0.873 nmol/L (0.252 ng/mL) for DHEA. For all the analytes, the lowest calibration point relative standard deviation was less than 10.8%, indicating a good precision of the assay within the lowest concentration of interest. In conclusion, in this method article, we describe a simple, sensitive, and cost-effective 2D-LC/MS/MS method suitable for the routine analysis of a complex of steroid hormones allowing high analytical specificity and sensitivity despite minimal sample processing and short throughput times.

The Genus Spinopygina gen. nov. (Diptera, Sciaridae) from Western North America: Preliminary Molecular Phylogeny and Description of Seven New Species.

The genus Spinopygina gen. nov. (type species Camptochaeta uniceps Hippa & Vilkamaa, 1994) from western North America is described. The genus includes the following eight species: Spinopygina acerfalx sp. nov.; S. aurifera sp. nov.; S. camura sp. nov.; S. edura sp. nov.; S. peltata sp. nov.; S. plena sp. nov.; S. quadracantha sp. nov.; and S. uniceps (Hippa & Vilkamaa, 1994) comb. nov., transferred from Corynoptera Winnertz. The new species are described and Spinopygina uniceps is re-diagnosed. The species are keyed and illustrated. In the maximum-likelihood phylogenetic hypothesis based on four gene fragments (28S, 18S, 16S and COI), Spinopygina gen. nov. appears as the sister group of Claustropyga Hippa, Vilkamaa & Mohrig, 2003. In the same analysis, a remarkable, undescribed species is placed within Camptochaeta Hippa & Vilkamaa clade.

Gene-rich X chromosomes implicate intragenomic conflict in the evolution of bizarre genetic systems.

Haplodiploidy and paternal genome elimination (HD/PGE) are common in invertebrates, having evolved at least two dozen times, all from male heterogamety (i.e., systems with X chromosomes). However, why X chromosomes are important for the evolution of HD/PGE remains debated. The Haploid Viability Hypothesis posits that X-linked genes promote the evolution of male haploidy by facilitating purging recessive deleterious mutations. The Intragenomic Conflict Hypothesis holds that conflict between genes drives genetic system turnover; under this model, X-linked genes could promote the evolution of male haploidy due to conflicts with autosomes over sex ratios and genetic transmission. We studied lineages where we can distinguish these hypotheses: species with germline PGE that retain an XX/X0 sex determination system (gPGE+X). Because evolving PGE in these cases involves changes in transmission without increases in male hemizygosity, a high degree of X linkage in these systems is predicted by the Intragenomic Conflict Hypothesis but not the Haploid Viability Hypothesis. To quantify the degree of X linkage, we sequenced and compared 7 gPGE+X species' genomes with 11 related species with typical XX/XY or XX/X0 genetic systems, representing three transitions to gPGE. We find highly increased X linkage in both modern and ancestral genomes of gPGE+X species compared to non-gPGE relatives and recover a significant positive correlation between percent X linkage and the evolution of gPGE. These empirical results substantiate longstanding proposals for a role for intragenomic conflict in the evolution of genetic systems such as HD/PGE.

A Peculiar New Genus of Bibionomorpha (Diptera) with Brachycera-Like Modification of Antennae from Mid-Cretaceous Amber of Myanmar.

A new fossil genus of Bibionidae (Diptera: Bibionomorpha), Burmahesperinus gen. nov., from the mid-Cretaceous Burmese amber, is described and illustrated (type species Burmahesperinus antennatus sp. nov., the other two species included are B. conicus sp. nov. and B. pedicellatus sp. nov.). The new genus is tentatively placed in a new subfamily, Burmahesperininae subfam. nov. of the family Bibionidae. Its possible phylogenetic position is briefly discussed. The new genus, as well as the subfamily, possesses the wing venation similar to the recent genus Hesperinus Walker, 1848, in combination with Brachycera-like modification of both the male and female antenna and the overall habitus typical of fungus gnats (Sciaroidea).

Fossils Shed a New Light on the Diversity and Disparity of the Family Limoniidae (Diptera, Nematocera).

A new subfamily Drinosinae (Diptera, Limoniidae) is established with two fossil genera, Drinosa and Decessia gen. nov. with one new species, Decessia podenasi gen. et sp. nov. from Cretaceous Burmese amber. Additional description of Drinosa prisca is based on new material. A new subfamily shows unique reduction of radial veins combined with complete set of medial veins.

Reinforcement of Colonic Anastomosis with Improved Ultrafine Nanofibrous Patch: Experiment on Pig.

Anastomotic leakage is a dreadful complication in colorectal surgery. It has a negative impact on postoperative mortality, long term life quality and oncological results. Nanofibrous polycaprolactone materials have shown pro-healing properties in various applications before. Our team developed several versions of these for healing support of colorectal anastomoses with promising results in previous years. In this study, we developed highly porous biocompatible polycaprolactone nanofibrous patches. We constructed a defective anastomosis on the large intestine of 16 pigs, covered the anastomoses with the patch in 8 animals (Experimental group) and left the rest uncovered (Control group). After 21 days of observation we evaluated postoperative changes, signs of leakage and other complications. The samples were assessed histologically according to standardized protocols. The material was easy to work with. All animals survived with no major complication. There were no differences in intestinal wall integrity between the groups and there were no signs of anastomotic leakage in any animal. The levels of collagen were significantly higher in the Experimental group, which we consider to be an indirect sign of higher mechanical strength. The material shall be further perfected in the future and possibly combined with active molecules to specifically influence the healing process.

Just a Fragment of Undescribed Diversity: Twenty New Oriental and Palearctic Species of Sciaroidea (Diptera), including DNA Sequence Data and Two New Fossil Genera.

The following 17 extant new species of Sciaroidea (Diptera: Bibionomorpha) are described: Bolitophila nikolae Sevcík sp. nov. (Bolitophilidae, Taiwan), Catocha jingfui sp. nov. (Cecidomyiidae, Taiwan), Catocha manmiaoe sp. nov. (Cecidomyiidae, Taiwan), Catocha shengfengi sp. nov. (Cecidomyiidae, Taiwan), Planetella taiwanensis sp. nov. (Cecidomyiidae, Taiwan), Diadocidia pseudospinusola sp. nov. (Diadocidiidae, Taiwan), Asioditomyia bruneicola sp. nov. (Ditomyiidae, Brunei), Asioditomyia lacii sp. nov. (Ditomyiidae, Taiwan), Ditomyia asiatica sp. nov. (Ditomyiidae, Thailand), Chetoneura davidi sp. nov. (Keroplatidae, Brunei), Euceroplatus mantici sp. nov. (Keroplatidae, Thailand), Setostylus fangshuoi sp. nov. (Keroplatidae, Taiwan), Platyceridion yunfui sp. nov. (Keroplatidae, Hainan), Terocelion adami sp. nov. (Keroplatidae, Taiwan), Hadroneura martini sp. nov. (Mycetophilidae, Taiwan), Paratinia furcata sp. nov. (Mycetophilidae, Czech Republic, Slovakia), and Nepaletricha sikorai sp. nov. (Sciaroidea incertae sedis, Thailand). Two new genera are described from the mid-Cretaceous Burmese amber, Burmasymmerus gen. nov. (Ditomyiidae, type species Burmasymmerus korneliae sp. nov., including also B. wieslawi sp. nov.), representing the first record of the family Ditomyiidae from the Mesozoic, and Burmatricha gen. nov. (Sciaroidea incertae sedis, type species Burmatricha mesozoica sp. nov.). Molecular phylogeny of Ditomyiidae, based on two DNA markers (28S, COI), as well as that of Catocha Haliday, 1833, based on the mitochondrial COI and 16S fragments, are also presented.

Extant Genus in the Mesozoic: Paleoplatyura Meunier (Diptera: Keroplatidae) Found in the Cretaceous Amber of Myanmar.

Three new species of Paleoplatyura Meunier, 1899, i.e., Paleoplatyura agnieszkae sp. nov., P. miae sp. nov., and P. magnifica sp. nov., are described and figured. The concept of the genus is briefly discussed, and its systematic position is clarified. A key to fossil species is provided. The genus Paleoplatyura is described from the Eocene Baltic amber. It is concluded that, in Baltic amber, this group is represented only by the type species, and the identity of the other two species is problematic. No additional specimens have been found so far in this amber. Therefore, the presence of as many as three new species in Burmese amber, certainly belonging to Paleoplatyura, is a confirmation of its occurrence already in the Mesozoic.

Intriguing and Beautiful: Adamacrocera adami gen. et sp. nov. from the Upper Cretaceous Amber of Myanmar Represents a New Subfamily of Keroplatidae (Diptera: Bibionomorpha).

A new fossil genus and species of Keroplatidae (Diptera, Bibionomorpha, Sciaroidea), Adamacrocera adami gen. et sp. nov., from the Upper Cretaceous Burmese amber is described and illustrated. Based on morphological evidence, it is placed in a new subfamily Adamacrocerinae subfam. nov. The new genus, as well as the subfamily, possesses the wing venation characteristic of the genera of some Sciaroidea incertae sedis, as well as that of the fossil families Archizelmiridae, Antefungivoridae and Mesosciophilidae, in combination with macrocerine-like habitus and male terminalia.

Hidden in Plain Sight: Comprehensive Molecular Phylogeny of Keroplatidae and Lygistorrhinidae (Diptera) Reveals Parallel Evolution and Leads to a Revised Family Classification.

We provide the first molecular phylogeny of Keroplatidae and Lygistorrhinidae, families of fungus gnats (Diptera: Bibionomorpha: Sciaroidea). Phylogenies reconstructed by Maximum Likelihood and Bayesian methods, based on four nuclear and four mitochondrial gene markers (5106 base pairs) sequenced for 75 genera and 105 species, show Keroplatidae as monophyletic only with the family Lygistorrhinidae included, herewith treated as the subfamily Lygistorrhininae stat. nov. The subfamily Arachnocampinae is retained in the family, although lowering its overall support. An early branching clade, comprising species of Platyura Meigen, 1803 and Paleoplatyura melanderi Fisher, 1941, forms subfamily Platyurinae Loew, 1850 stat. nov. The subfamilies Sciarokeroplatinae and Macrocerinae grouped together with three genera considered here as Keroplatidae incertae sedis. Subfamily Lygistorrhininae forms a sister clade to subfamily Keroplatinae, both retained monophyletic with high support. The traditional division of the subfamily Keroplatinae into the tribes Orfeliini and Keroplatini appears as outdated, resting largely on adaptive characters prone to parallel evolution. We find support for an alternative tribe corresponding to the Cloeophoromyia-Asindulum genus group, but a tribal reclassification of the Keroplatinae is left for future studies. The genus Heteropterna Skuse, 1888 is considered as identical with Ctenoceridion Matile, 1972 syn. nov.

Identification of novel HNF1B mRNA splicing variants and their qualitative and semi-quantitative profile in selected healthy and tumour tissues.

Hepatocyte nuclear factor-1-beta (HNF1B) is a transcription factor crucial for the development of several tissues, and a promising biomarker of certain solid tumours. Thus far, two HNF1B alternative splicing variants (ASVs) have been described, however, the complete spectrum, prevalence and role of HNF1B ASVs in tumorigenesis are unclear. Considering the equivocal data about HNF1B ASVs and expression presented in literature, our aim was to characterize the spectrum of HNF1B mRNA splicing variants across different tissues. Here, we characterize HNF1B ASVs with high sensitivity in carcinomas of the uterine corpus, large intestine, kidney, pancreas, and prostate, with selected paired healthy tissues, using the previously described multiplex PCR and NGS approach. We identified 45 ASVs, of which 43 were novel. The spectrum and relative quantity of expressed ASVs mRNA differed among the analysed tissue types. Two known (3p, Δ7_8) and two novel (Δ7, Δ8) ASVs with unknown biological functions were detected in all the analysed tissues in a higher proportion. Our study reveals the wide spectrum of HNF1B ASVs in selected tissues. Characterization of the HNF1B ASVs is an important prerequisite for further expression studies to delineate the HNF1B splicing pattern, potential ASVs functional impact, and eventual refinement of HNF1B's biomarker role.

Cabamofa orientalis sp. nov. from Thailand, congeneric with C. mira Jaschhof from Costa Rica (Diptera: Bibionomorpha: Sciaroidea incertae sedis).

The genus Cabamofa, previously containing only C. mira from Costa Rica (Jaschhof 2005), is shown here to have a second species in Thailand, which is described and named C. orientalis sp. nov. The new species is known from a single male collected by the TIGER Project (Thailand Inventory Group for Entomological Research), a mass-sampling program to inventory insect diversity in Southeast Asia (Plant et al. 2011; http://sharkeylab.org/tiger, accessed 14 December 2018). As the circumstances of finding indicate, C. orientalis is a decidedly rare species, an attribute applying to perhaps one third of all tropical arthropods (Lim et al. 2012) and most Sciaroidea incertae sedis (Jaschhof 2017), including the Costa Rican C. mira. The latter species was originally described from two females, which were Malaise trapped in 2003 in lowland rain forest (Jaschhof 2005), while a conspecific male, a museum specimen collected in 1922 in an unknown habitat, was detected and described subsequently (Amorim Rindal 2007). Cabamofa is one of nearly 20 sciaroid genera whose family affiliation has not yet been resolved (Jaschhof 2017), but there is morphological evidence suggesting its close affinity to other Sciaroidea incertae sedis, such as Rogambara Jaschhof, 2005, Ohakunea Tonnoir Edwards, 1927, and Colonomyia Colless, 1963. These four genera together form the Ohakunea group of Jaschhof (2005), or the Ohakuneinae (as a subfamily of the broadly conceived family Rangomaramidae) of Amorim Rindal (2007). Recent molecular work (Sevcík et al. 2016, Kasprák et al. 2019) suggests a more distant phylogenetic position of Ohakunea to other Sciaroidea incertae sedis. The obvious conflict here between morphological and molecular evidence is stimulating fresh interest in the "incertae sedis issue", as proven by the present contribution. The morphology of C. orientalis provides no new clues as to the systematic position of Cabamofa, or the Ohakunea group, but reveals characters that were previously not known to occur in Cabamofa. The delimitation of this genus is briefly reviewed below. Our finding of C. orientalis extends the geographic distribution of Cabamofa from the New World to the Old World (Oriental) tropics, which consorts with the disjunct (Neotropical-Australasian) areas found in both Colonomyia and Ohakunea. Morphological terminology used here is in accordance with that by Cumming Wood (2017).

Review of Pseudoaerumnosa Rudzinski (Diptera, Sciaridae), with the description of twenty-four new species.

The genus Pseudoaerumnosa Rudzinski, 2006 is redefined. The genus includes the following species which are described, illustrated and keyed: Pseudoaerumnosa acinacea sp. n., P. ampliata sp. n., P. annae sp. n., P. awanensis sp. n., P. banari sp. n., P. clavidactyla sp. n., P. clivicola sp. n., P. collicola sp. n., P. consuota sp. n., P. cryptoloba sp. n., P. curvifalx sp. n., P. eminula sp. n., P. exacuta sp. n., P. filispicata sp. n., P. formosa sp. n., P. fragilis sp. n., P. impensa sp. n., P. inviolata Rudzinski, 2006, P. junciseta sp. n., P. obovata sp. n., P. pilicaudata sp. n., P. quadriquetra sp. n., P. saginata sp. n., P. tenuidens sp. n. and P. tkoci sp. n. Morphological characters and the phylogenetic position of Pseudoaerumnosa are discussed. For some species, the barcode (COI) sequence data were obtained. The genus is currently known from the Oriental (22 species), Malagasy (3 species) and Australasian regions (1 species).

Germline CHEK2 Gene Mutations in Hereditary Breast Cancer Predisposition - Mutation Types and their Biological and Clinical Relevance.

BACKGROUND: Hereditary mutations in the CHEK2 gene (which encodes CHK2 kinase) contribute to a moderately increased risk of breast cancer (BC) and other cancers. Large variations in the frequency of CHEK2 mutations and the occurrence of variants of unknown clinical significance (VUS) complicate estimation of cancer risk in carriers of germline CHEK2 mutations. PATIENTS AND METHODS: We performed mutation analysis of 1,526 high-risk Czech BC patients and 3,360 Czech controls. Functional analysis was performed for identified VUS using a model system based on a human RPE1-CHEK2-KO cell line harboring biallelic inactivation of endogenous CHEK2. RESULTS: The frequency of ten truncating CHEK2 variants differed markedly between BC patients (2.26%) and controls (0.11%; p = 4.1 × 1012). We also found 23 different missense variants in 4.5% patients and in 4.0% of controls. The most common was p.I157T, which was found in patients and controls with the same frequency. Functional analysis identified nine functionally deleterious VUS, another nine functionally neutral VUS, and four intermediate VUS (including p.I157T). We found that carriers of truncating CHEK2 mutations had a high BC risk (OR 8.19; 95% CI 4.11-17.75), and that carriers of functionally deleterious missense variants had a moderate risk (OR 4.06; 95% CI, 1.37-13.39). Carriers of these mutations developed BC at 44.4 and 50.7 years, respectively. Functionally neutral and functionally intermediate missense variants did not increase the BC risk. BC in CHEK2 mutation carriers was frequently ER-positive and of higher grade. Notably, carriers of CHEK2 mutations developed second cancers more frequently than BRCA1/BRCA2/PALB2/p53 or mutation non-carriers. CONCLUSION: Hereditary CHEK2 mutations contribute to the development of hereditary BC. The associated cancer risk in mutation carriers increases with the number of affected individuals in a family. Annual follow-up with breast ultrasound, mammography, or magnetic resonance imaging is recommended for asymptomatic mutation carriers from the age of 40. Surgical prevention and specific follow-up of other tumors should be considered based on family cancer history. The work was supported by grants from the Czech Health Research Council of the Ministry of Health of the Czech Republic NR 15-28830A, 16-29959A, NV19-03-00279, projects of the PROGRES Q28/LF1, GAUK 762216, SVV2019 / 260367, PRIMUS/17/MED/9, UNCE/MED/016, Progress Q26, LQ1604 NPU II and project AVČR Qualitas. The analysis of a set of unselected controls was made possible by the existence and support of the scientific infrastructure of the National Center for Medical Genomics (LM2015091) and its project aimed at creating a reference database of genetic variants of the Czech Republic (CZ.02.1.01/0.0/0.0/16_013/0001634). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 2. 4. 2019 Accepted: 14. 5. 2019.

Taxi drivers: the role of animals in transporting mycorrhizal fungi.

Dispersal of mycorrhizal fungi via animals and the importance for the interacting partners' life history as well as for ecosystems is an understudied topic. In this review, we describe the available evidence and the most important knowledge gaps and finally suggest ways to gain the missing information. So far, 33 articles have been published proving a successful transfer of mycorrhizal propagules by animals. The vast majority of research on invertebrates was focused on arbuscular mycorrhizal (AM) fungi, whereas papers on vertebrates (mainly rodents and artiodactyls) equally addressed ectomycorrhizal (ECM) and AM fungi. Effective dispersal has been mostly shown by the successful inoculation of bait plants and less commonly by spore staining or germination tests. Based on the available data and general knowledge on animal lifestyles, collembolans and oribatid mites may be important in transporting ECM fungal propagules by ectozoochory, whereas earthworms, isopods, and millipedes could mainly transfer AM fungal spores in their gut systems. ECM fungal distribution may be affected by mycophagous dipterans and their hymenopteran parasitoids, while slugs, snails, and beetles could transport both mycorrhizal groups. Vertebrates feeding on fruit bodies were shown to disperse mainly ECM fungi, while AM fungi are transported mostly accidentally by herbivores. The important knowledge gaps include insufficient information on dispersal of fungal propagules other than spores, the role of invertebrates in the dispersal of mycorrhizal fungi, the way in which propagules pass through food webs, and the spatial distances reached by different dispersal mechanisms both horizontally and vertically.

Identification of deleterious germline CHEK2 mutations and their association with breast and ovarian cancer.

Germline mutations in checkpoint kinase 2 (CHEK2), a multiple cancer-predisposing gene, increase breast cancer (BC) risk; however, risk estimates differ substantially in published studies. We analyzed germline CHEK2 variants in 1,928 high-risk Czech breast/ovarian cancer (BC/OC) patients and 3,360 population-matched controls (PMCs). For a functional classification of VUS, we developed a complementation assay in human nontransformed RPE1-CHEK2-knockout cells quantifying CHK2-specific phosphorylation of endogenous protein KAP1. We identified 10 truncations in 46 (2.39%) patients and in 11 (0.33%) PMC (p = 1.1 × 10-14 ). Two types of large intragenic rearrangements (LGR) were found in 20/46 mutation carriers. Truncations significantly increased unilateral BC risk (OR = 7.94; 95%CI 3.90-17.47; p = 1.1 × 10-14 ) and were more frequent in patients with bilateral BC (4/149; 2.68%; p = 0.003), double primary BC/OC (3/79; 3.80%; p = 0.004), male BC (3/48; 6.25%; p = 8.6 × 10-4 ), but not with OC (3/354; 0.85%; p = 0.14). Additionally, we found 26 missense VUS in 88 (4.56%) patients and 131 (3.90%) PMC (p = 0.22). Using our functional assay, 11 variants identified in 15 (0.78%) patients and 6 (0.18%) PMC were scored deleterious (p = 0.002). Frequencies of functionally intermediate and neutral variants did not differ between patients and PMC. Functionally deleterious CHEK2 missense variants significantly increased BC risk (OR = 3.90; 95%CI 1.24-13.35; p = 0.009) and marginally OC risk (OR = 4.77; 95%CI 0.77-22.47; p = 0.047); however, carriers low frequency will require evaluation in larger studies. Our study highlights importance of LGR detection for CHEK2 analysis, careful consideration of ethnicity in both cases and controls for risk estimates, and demonstrates promising potential of newly developed human nontransformed cell line assay for functional CHEK2 VUS classification.